MCF-7 Human Breast Carcinoma Research Articles

Synthesis and Cytotoxic Activity of Ursolic Acid Derivatives

10-15 Fourteen ursolic acid derivatives, among them four novel compounds, were synthesized by modification either at the C-3, C-28 or both positions. The cytotoxic activity of the obtained derivatives was evaluated against the four human cancer cell lines KB (human mouth epidermal carcinoma), HepG2 (human hepatocellular carcinoma), MCF7 (human breast carcinoma) and Lu (human lung carcinoma). As the result, compounds 7and 8were from two to three times more active than ursolic acid on all four tested cell lines. This is the first report on cytotoxic effects of the synthetized ursolic acid derivatives 4, 8, and .

Newcastle disease virus Malaysian strain AF2240 induces apoptosis in MCF-7 human breast carcinoma cells at an early stage of the virus life cycle

Newcastle disease virus (NDV) AF2240 Malaysian strain is a very virulent avian virus. NDV strain AF2240 was previously demonstrated to induce apoptosis in human breast carcinoma MCF-7 cells. However, at which stage of the NDV life cycle apoptosis is induced and whether NDV replication and protein synthesis are involved in apoptosis induction have yet to be determined. In the present study, we investigated the time course of NDV strain AF2240 nucleoprotein (NP) gene expression and the early apoptotic signs in the form of activation of caspase-8 and mitochondrial transition pore opening. In addition, the induction of apoptosis by both ultraviolet-inactivated and cycloheximide-treated NDV-infected MCF-7 cells were examined. Our findings showed that NDV strain AF2240 induced apoptosis at 1h post-infection (pi) through activation of mitochondrial transition pore opening and at 2h through activation of caspase-8, while the NP gene was expressed at 6h pi. The induced apoptosis was independent of both virus replication and protein synthesis. In conclusion, NDV strain AF2240 induces apoptosis at an early stage of its life cycle, possibly during virus binding or fusion with the cell membrane. The mitochondrial-related pathway may be the central activator in NDV strain AF2240-induced apoptosis.

Identification of novel caspase/autophagy‐related gene switch to cell fate decisions in breast cancers

Caspases, a family of cysteine proteases with unique substrate specificities, contribute to apoptosis, whereas autophagy-related genes (ATGs) regulate cytoprotective autophagy or autophagic cell death in cancer. Accumulating evidence has recently revealed underlying mechanisms of apoptosis and autophagy; however, their intricate relationships still remain to be clarified. Identification of caspase/ATG switches between apoptosis and autophagy may address this problem. Identification of caspase/ATG switches was carried out using a series of elegant systems biology & bioinformatics approaches, such as network construction, hub protein identification, microarray analyses, targeted microRNA prediction and molecular docking. We computationally constructed the global human network from several online databases and further modified it into the basic caspase/ATG network. On the basis of apoptotic or autophagic gene differential expressions, we identified three molecular switches [including androgen receptor, serine/threonine-protein kinase PAK-1 (PAK-1) and mitogen-activated protein kinase-3 (MAPK-3)] between certain caspases and ATGs in human breast carcinoma MCF-7 cells. Subsequently, we identified microRNAs (miRNAs) able to target androgen receptor, PAK-1 and MAPK-3, respectively. Ultimately, we screened a range of small molecule compounds from DrugBank, able to target the three above-mentioned molecular switches in breast cancer cells. We have systematically identified novel caspase/ATG switches involved in miRNA regulation, and predicted targeted anti-cancer drugs. These findings may uncover intricate relationships between apoptosis and autophagy and thus provide further new clues towards possible cancer drug discovery.

Tumor cell-macrophage interactions increase angiogenesis through secretion of EMMPRIN

Tumor macrophages are generally considered to be alternatively/M2 activated to induce secretion of pro-angiogenic factors such as VEGF and MMPs. EMMPRIN (CD147, basigin) is overexpressed in many tumor types, and has been shown to induce fibroblasts and endothelial cell expression of MMPs and VEGF. We first show that tumor cell interactions with macrophages resulted in increased expression of EMMPRIN and induction of MMP-9 and VEGF. Human A498 renal carcinoma or MCF-7 breast carcinoma cell lines were co-cultured with the U937 monocytic-like cell line in the presence of TNFα (1 ng/ml). Membranal EMMPRIN expression was increased in the co-cultures (by 3–4-folds, p < 0.01), as was the secretion of MMP-9 and VEGF (by 2–5-folds for both MMP-9 and VEGF, p < 0.01), relative to the single cultures with TNFα. Investigating the regulatory mechanisms, we show that EMMPRIN was post-translationally regulated by miR-146a, as no change was observed in the tumoral expression of EMMPRIN mRNA during co-culture, expression of miR-146a was increased and its neutralization by its antagomir inhibited EMMPRIN expression. The secretion of EMMPRIN was also enhanced (by 2–3-folds, p < 0.05, only in the A498 co-culture) via shedding off of the membranal protein by a serine protease that is yet to be identified, as demonstrated by the use of wide range protease inhibitors. Finally, soluble EMMPRIN enhanced monocytic secretion of MMP-9 and VEGF, as inhibition of its expression levels by neutralizing anti-EMMPRIN or siRNA in the tumor cells lead to subsequent decreased induction of these two pro-angiogenic proteins. These results reveal a mechanism whereby tumor cell-macrophage interactions promote angiogenesis via an EMMPRIN-mediated pathway.

Zinc(ii) complexes containing bis-benzimidazole derivatives as a new class of apoptosis inducers that trigger DNA damage-mediated p53 phosphorylation in cancer cells

In the present study, two zinc(II) complexes containing bis-benzimidazole derivatives, Zn(bpbp)Cl2 (1) and [Zn(bpbp)2](ClO4)2·CH3CH2OH·H2O (2) (bpbp = 2,6-bis(1-phenyl-1H-benzo[d]imidazol-2-yl)pyridine), have been designed, synthesized and evaluated for their in vitro anticancer activities. The underlying molecular mechanisms through which they caused the cancer cell death were also elucidated. The complexes were identified as potent antiproliferative agents against a panel of five human cancer cell lines by comparing with cisplatin. Complex 2 demonstrated dose-dependent growth inhibition on MCF-7 human breast carcinoma cells with IC50 at 2.9 μM. Despite this potency, the complexes possessed great selectivity between human cancer cells and normal cells. Induction of apoptosis in MCF-7 cells by complex 2 was evidenced by accumulation of sub-G1 cell population, DNA fragmentation and nuclear condensation. Further investigation on intracellular mechanisms revealed that complex 2 was able to induce p53-dependent apoptosis in cancer cells by triggering DNA damage. On the basis of this evidence, we suggest that Zn(II) complexes containing bis-benzimidazole derivatives may be candidates for further evaluation as chemotherapeutic agents for human cancers.

Abstract P6-04-27: EBAG9 immunoreactivity is a potential prognostic factor for poor outcome of breast cancer patients with adjuvant tamoxifen therapy

Abstract Estrogen receptor-binding fragment associated gene 9 (EBAG9) is a primary estrogen responsive gene originally cloned from MCF-7 human breast carcinoma cells. Upregulation of EBAG9 expression has been observed in several malignant tumors such as advanced breast cancers, indicating that EBAG9 may contribute to tumor progression. In the present study, the immunohistochemical analyses of EBAG9 were performed using the specimens from breast cancer patients treated with tamoxifen as adjuvant therapy. To investigate the association between EBAG9 expression and the therapeutic effect of tamoxifen in breast cancer, we used adjuvant tamoxifen-treated breast cancer patient tissues from 3 institutions. The study was approved by the institutional review board. Patients with distant metastases within 5 years after surgery followed by tamoxifen treatment were defined as relapse cases, whereas those without distant metastases were defined as relapse-free cases. The immunoreactivity of EBAG9 was predominantly detected in the cytoplasm of breast cancer cells. Notably, EBAG9 immunoreactivity level was substantially elevated in the breast cancer samples from the relapse patients, and the positive immunoreactivity of EBAG9 was correlated with poor prognosis of the patients with adjuvant therapy. These results suggest that EBAG9 expression in tumor regions is associated with unfavorable prognosis of patients with adjuvant tamoxifen therapy and EBAG9 immunoreactivity can serve as a biomarker for adjuvant tamoxifen efficacy. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-04-27.

Evaluation of biological activities of a groundnut (Apios americana Medik) extract containing a novel isoflavone

Groundnut (Apios americana Medik) contains a novel isoflavone, genistein-7-O-gentiobioside. In the present study, we examined the biological activities of an alcohol extract of groundnut containing genistein-7-O-gentiobioside as the main component. Although the groundnut extract by itself did not show antioxidative activity, it drove the antioxidative system in cells. Pretreatment of human breast carcinoma MCF-7 cells for 24h with the groundnut extract and soybean isoflavone increased gene expression of heme oxygenase-1 (HO-1), a major antioxidative stress enzyme. These groundnut extract-treated cells showed antioxidative activity against free radicals derived from a radical initiator. Pretreatment of cells with 100μg/mL groundnut extract prevented the depletion of glutathione by the radical initiator; however, treatment with 100μg/mL of soybean isoflavone injured the cell membrane, indicating that glutathione might be released to the extracellular environment. These results suggest that the groundnut extract had isoflavone-like activity. Like soybean, groundnuts are a good source of isoflavones.

Three-Dimensional-Engineered Matrix to Study Cancer Stem Cells and Tumorsphere Formation: Effect of Matrix Modulus

Maintenance of cancer stem cells (CSCs) is regulated by the tumor microenvironment. Synthetic hydrogels provide the flexibility to design three-dimensional (3D) matrices to isolate and study individual factors in the tumor microenvironment. The objective of this work was to investigate the effect of matrix modulus on tumorsphere formation by breast cancer cells and maintenance of CSCs in an inert microenvironment without the interference of other factors. In that regard, 4T1 mouse breast cancer cells were encapsulated in inert polyethylene glycol diacrylate hydrogels and the effect of matrix modulus on tumorsphere formation and expression of CSC markers was investigated. The gel modulus had a strong effect on tumorsphere formation and the effect was bimodal. Tumorsphere formation and expression of CSC markers peaked after 8 days of culture. At day 8, as the matrix modulus was increased from 2.5 kPa to 5.3, 26.1, and 47.1 kPa, the average tumorsphere size changed from 37±6 μm to 57±6, 20±4, and 12±2 μm, respectively; cell number density in the gel changed from 0.8±0.1×10⁵ cells/mL to 1.7±0.2×10⁵, 0.4±0.1×10⁵, and 0.2±0.1×10⁵ cells/mL after initial encapsulation of 0.14×10⁵ cells/mL; and the expression of CD44 breast CSC marker changed from 17±4-fold to 38±9-, 3±1-, and 2±1-fold increase compared with the initial level. Similar results were obtained with MCF7 human breast carcinoma cells. Mouse 4T1 and human MCF7 cells encapsulated in the gel with 5.3 kPa modulus formed the largest tumorspheres and highest density of tumorspheres, and had highest expression of breast CSC markers CD44 and ABCG2. The inert polyethylene glycol hydrogel can be used as a model-engineered 3D matrix to study the role of individual factors in the tumor microenvironment on tumorigenesis and maintenance of CSCs without the interference of other factors.

MUC-1 aptamer-conjugated dye-doped silica nanoparticles for MCF-7 cells detection

In this work, we have prepared three types of aptamer-conjugated Rubpy-doped silica nanoparticles for Human breast carcinoma MCF-7 cells labeling. Probe A is prepared through covalent conjugation between amine-labeled MUC-1 aptamer and carboxyl-modified Rubpy-doped NPs (NPs-aptamer). Probe B is prepared based on the interaction between biotin-labeled MUC-1 aptamer and avidin-conjugated Rubpy-doped NPs (NPs-avidin-biotin-aptamer). For Probe C, there is a PEG with flexible long chain as the bridge between avidin and the NPs (NPs-PEG-avidin-biotin-aptamer). In addition, we further investigate the practical number of MUC-1 aptamers on an NP of each probe using hoechst33258 dye. The binding efficiency of MUC-1 aptamer on the three types of probes as follows: Probe A < Probe B < Probe C. In addition, microscopic fluorescence imaging shows that Probe C containing the PEG molecules can be effectively applied for the recognition of MUC-1 protein in human breast carcinoma MCF-7 cells thus demonstrates that the PEG with flexible long chain as the bridge between the aptamer and NP can greatly enhances the freedom of MUC-1 aptamer. Compared with common organic dyes, the dye-doped silica nanoparticles serve as a stable bioprobe because of their facile conjugation with the desirable biomolecules, and have exhibited great potential in bioanalysis.

Synthesis and biological evaluation of imidazo[4,5-b]pyridine and 4-heteroaryl-pyrimidine derivatives as anti-cancer agents

A series of N-phenyl-imidazo[4,5-b]pyridin-2-amines, 4-indazolyl-N-phenylpyrimidin-2-amines and N-phenyl-4-pyrazolo[3,4-b]pyridin-pyrimidin-2-amines have been synthesized. Their anti-proliferative activities were tested in HCT-116 human colon carcinoma and MCF-7 breast carcinoma cell lines. Many exhibited potent anti-proliferative and CDK9 inhibitory activities. A lead compound 18b demonstrated the ability to reduce the level of Mcl-1 anti-apoptotic protein, to activate caspase 3/7 and induce cancer cell apoptosis.

Expression of Peroxiredoxin 1, 2, 3, and 6 Genes in Cancer Cells during Drug Resistance Formation

We studied the expression of peroxiredoxin genes (PRDX1, PRDX2, PRDX3, and PRDX6) in human erythroleukemia K652, human breast carcinoma MCF-7, and human ovarian carcinoma SKOV-3 cells during cisplatin resistance development. It was found that drug resistance formation was accompanied by a significant increase in the expression of PRDX1, PRDX2, PRDX3, PRDX6 genes in all cancer cell strains, which confirms the important contribution of redox-dependent mechanisms into the development of cisplatin resistance of cancer cells.

Identification of microRNA-regulated autophagic pathways in plant lectin-induced cancer cell death.

Plant lectins, carbohydrate-binding proteins of non-immune origin, have recently been reported to induce programmed cell death (including apoptosis and autophagy) in many types of cancer cells. MicroRNAs (miRNAs), small, non-coding endogenous RNAs, ~22 nucleotides (nt) in length, have been well characterized to play essential roles in regulation of the autophagy process in cancer; however, how these miRNAs regulate autophagic pathways in plant lectin-induced cancer cells, still remains an enigma. Identification of microRNA-regulated autophagic pathways was carried out using a series of elegant systems - biology and bioinformatics approaches, such as network construction, hub protein identification, targeted microRNA prediction, microarray analyses and molecular docking. We computationally constructed the human autophagic protein-protein interaction (PPI) network, and further modified this network into a plant lectin-induced network. Subsequently, we identified 9 autophagic hub proteins and 13 relevant oncogenic and tumour suppressive miRNAs, that could regulate these aforementioned targeted autophagic hub proteins, in human breast carcinoma MCF-7 cells. In addition, we confirmed that plant lectins could block the sugar-containing receptor EGFR-mediated survival pathways, involved in autophagic hub proteins and relevant miRNAs, thereby ultimately culminating in autophagic cell death. These results demonstrate that network-based identification of microRNAs modulate autophagic pathways in plant lectin-treated cancer cells, which may shed new light on the discovery of plant lectins as potent autophagic inducers, for cancer drug discovery.

Nanoemulsion-templated multilayer nanocapsules for cyanine-type photosensitizer delivery to human breast carcinoma cells

There is great clinical interest in developing novel nanocarriers for hydrophobic cyanine dyes used as photosensitizing agents in photodynamic therapy (PDT). In the present study we have employed nanoemulsion-templated oil-core multilayer nanocapsules as robust nanocarriers for a cyanine-type photosensitizer IR-786. These nanoproducts were fabricated via layer-by-layer (LbL) adsorption of oppositely charged polyelectrolytes (PEs), i.e., anionic PSS and cationic PDADMAC on nanoemulsion liquid cores created by dicephalic or bulky saccharide-derived cationic surfactants. All nanocapsules, with different thicknesses of the PE shell and average size <200nm (measured by DLS) demonstrated good capacity for IR-786 encapsulation. The nanocarriers were visualized by SEM and AFM and their photo-induced anticancer effect and cellular internalization in human breast carcinoma MCF-7/WT cells were determined. Biological response of the cell culture, expressed as dark and photocytotoxicity as well as fluorescence of drug molecules loaded in the multilayer vehicles, analyzed by the FACS and CLSM techniques, have indicated that the delivered IR-786 did not aggregate inside the cells and could, therefore, act as an effective third-generation photosensitizing agent. In vitro biological experiments demonstrated that the properties of studied nanostructures depended upon the PE type and the envelope thickness as well as on the surfactant architecture in the nanoemulsion-based templates employed for the nanocapsule fabrication. Similarity of results obtained for stored (three weeks in the dark at room temperature) and freshly-prepared nanocapsules, attests to viability of this stable, promising drug delivery system for poorly water-soluble cyanines useful in PDT.

Cytotoxic constituents from the fungus Daldinia concentrica (Xylariaceae)

Phytochemical study on the methanol extract of the fruit bodies of Vietnamese fungus Daldinia concentrica has led to the isolation and structural elucidation of three cytotoxic constituents, 6,8-dihydroxy-3-methyl-3,4-dihydroisocoumarin (1), (22R)-hydroxylanosta-7,9(11),24-trien-3-one (2) and ergosterol (3). Their structures were elucidated by 2D-NMR and FT-ICR-MS. All the three compounds showed moderate cytotoxicity against four cancer cells, KB (a human epidermal carcinoma), MCF7 (human breast carcinoma), SK-LU-1 (human lung carcinoma) and HepG2 (hepatocellular carcinoma). In addition, the isocoumarin (1) inhibited the growth of Staphylococcus aureus with the IC50 value of 87.81 µg mL−1.

JNK-dependent Atg4 upregulation mediates asperphenamate derivative BBP-induced autophagy in MCF-7 cells

N-Benzoyl-O-(N′-(1-benzyloxycarbonyl-4-piperidiylcarbonyl) -D-phenylalanyl)-D-phenylalaninol (BBP), a novel synthesized asperphenamate derivative with the increased solubility, showed growth inhibitory effect on human breast carcinoma MCF-7 cells in a time- and concentration-dependent manner. The growth inhibitory effect of BBP was associated with induction of autophagy, which was demonstrated by the development of acidic vesicular organelles, cleavage of LC3 and upregulation of Atg4 in BBP-treated MCF-7 cells. Since the application of Atg4 siRNA totally blocked the cleavage of LC3, we demonstrated a central role of Atg4 in BBP-induced autophagy. The further studies showed that BBP increased the levels of reactive oxygen species (ROS), and pretreatment with NAC effectively blocked the accumulation of ROS, autophagy and growth inhibition triggered by BBP. Moreover, BBP induced the activation of JNK, and JNK inhibitor SP600125 reversed autophagy, the increase of Atg4 levels, conversion of LC3 and growth inhibition induced by BBP. Knockdown of JNK by siRNA efficiently inhibited ROS production and autophagy, but antioxidant NAC failed to block JNK activation induced by BBP, indicating that JNK activation may be a upstream signaling of ROS and should be a core component in BBP-induced autophagic signaling pathway. These results suggest that BBP produces its growth inhibitory effect through induction of the autophagic cell death in MCF-7 cells, which is modulated by a JNK-dependent Atg4 upregulation involving ROS production.

Reversion of Multidrug Resistance in a Chemoresistant Human Breast Cancer Cell Line by β-Elemene

Background: Multidrug resistance (MDR) presents a problem in cancer chemotherapy, and developing new agents to overcome MDR is important. This study intends to investigate the reversal effect of β-elemene on MDR in human breast carcinoma MCF-7 and doxorubicin-resistant MCF-7 cells. Methods: MTT cytotoxicity assays, flow cytometry, and Western blot analysis were performed to investigate the antiproliferative effects of the combination of anticancer drugs with β-elemene, to study the reversal of drug resistance, and to examine the inhibitory effects on protein expression. Results: The results showed that β-elemene (30 µmol/l) had a strong potency to increase the cytotoxicity of doxorubicin to MCF-7/DOX cells, with a reversal fold of 6.38. In addition, the mechanisms of β-elemene in reversing P-glycoprotein (P-gp)-mediated MDR demonstrated that β-elemene significantly increases the intracellular accumulations of doxorubicin and Rh123 via inhibition of the P-gp transport function in MCF-7/DOX cells. Flow cytometry and Western blot analyses revealed that β-elemene could inhibit the expression of P-gp, while it had little effect on the expression of MRP1 protein. In addition, β-elemene had little inhibitory effect on the intracellular GSH levels and GST activities in MCF-7/DOX cells. Conclusions: β-Elemene might represent a promising agent for overcoming MDR in cancer therapy.

Abstract 5658: Engineered Salmonella effectively produce and preferentially deliver bacterial cytotoxins to solid tumors

Abstract To effectively treat cancer, therapeutics must specifically target tumor tissue and impart minimal toxicity to healthy tissues. Bacterial toxins, such as Pseudomonas aeruginosa Exotoxin A (PEA) and Staphylococcus aureus Alpha-Hemolysin (SAH), are highly cytotoxic and are promising moieties for cancer treatment. Due to their high toxicity and non-specificity towards all cells types, systemic effects limit their effectiveness as a therapeutic. While efforts have been made to impart cancer-cell specificity to these potent molecules, especially through immunotoxin technology, systemic toxicities still prove to be a challenge. Genetically engineered bacteria, such as Salmonella typhimurium, are known to target cancer by preferential accumulation within tumors and thus can be exploited as tumor-specific drug delivery vectors. By using cellular engineering techniques, the genetic machinery of bacteria can be used to produce exogenous bacterial toxins in situ. In addition to the specificity of bacterial accumulation, inducible promoter systems such as the arabinose-inducible system can be used to minimize systemic toxin levels by controlling the timing of protein expression. By coupling these strategies, we have been able to develop an effective bacterial therapy for targeted tumor treatment. PEA and SAH expressed in Salmonella under the PBAD promoter was secreted into the culture medium following arabinose induction. Monolayer cultures of MCF7 human breast carcinoma cells treated with secreted PEA and SAH for three days were depleted by 82% and 99%, respectively. Mechanism of delivery studies in a murine tumor model showed co-localization of salmonella, toxins and cell death within tumors following arabinose induction, while minimizing the localization of toxins to the healthy organs. Survival studies indicate that bacterial delivery of PEA and SAH can minimize systemic toxicities while decreasing tumor growth and increasing survival. Overall, these data indicate that by using bacteria to produce toxins in situ, we were able to overcome the delivery challenges inherent with non-specific toxin moieties and create a highly efficacious drug delivery system for use in the treatment of solid tumors. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5658. doi:1538-7445.AM2012-5658

Optimum HPLC parameters for simultaneous determination of Robinin and Kaempferol

An HPLC method for simultaneous quantitative determination of robinin and its aglycone kaempferol in MCF-7 human breast carcinoma cell line was developed. Robinin and kaempferol were separated using a Platinum EPS C-18 column (4.6 × 250 nm, 5 μm particle size). The detector was set at 380 nm. The mobile phase consisted of solution A [5 % MeOH in phosphate buffer (0.01 M, pH 2.0)] and solution B (THF:i-PrOH:MeOH:H2O, 150:200:67.5:32.5) in a 60:40 ratio (A:B). Calibration curves for both compounds were linear (R 2 = 0.9997, R 2 = 1) in the concentration range 25 – 1000 ng/mL. The intra- and interday variation coefficients were 1.31 – 8.92 %. The mean recoveries were 97.3 – 104.6 %. Robinin, a flavonoid glycoside isolated from leaves and flowers of Astragalus falcatus, decreases residual nitrogen, creatine, and urea in blood. The finished tablet dosage form prepared from it, flaronin, is used to treat uremia caused by chronic kidney failure.

Iodine catalyzed one-pot synthesis of chloro-substituted linear and angular indoloquinolines and in vitro antiproliferative activity study of different indoloquinolines

This article describes a facile one-pot synthesis of different chloro-substituted linear and angular indoloquinolines using iodine as a catalyst and in vitro antiproliferative activity of these chloro-substituted indoloquinolines (3e and 3f) and some indolo[2,3-b]quinolines (3a–d) against human hepatocellular carcinoma HepG2 and human breast carcinoma MCF-7 cells. Anti-proliferative assay against human hepatocellular carcinoma HepG2 and human breast carcinoma MCF-7 cells indicated methyl-substituted 6H-indolo[2,3-b]quinoline 3c to be the most active and the parent 6H-indolo[2,3-b]quinoline 3a to be the least active, while the other compounds including the different chloro derivatives exhibited only intermediate activity.

Synthesis and biological evaluation of novel steroidal[17,16-d][1,2,4]triazolo[1,5-a]pyrimidines

The preparation of steroidal[17,16-d][1,2,4]triazolo[1,5-a]pyrimidines and their biological evaluation as potential anticancer agents are herein reported. These novel heterosteroids (2, 4) were prepared through the condensation reaction of 3-amino-1,2,4-triazole with 16-arylidene-17-ketosteroids (1, 3). All the synthesized compounds were evaluated for their anticancer activity in vitro against PC-3 (human prostatic carcinoma), MCF-7 (human breast carcinoma) and EC9706 (human esophageal carcinoma) cell lines. Among the screened compounds, 2i, 2n and 4f showed significant inhibitory activity against all the three human cell lines.